Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

1 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

1 1 Some radionuclide lists are not 

complete. This is especially 

important for atmospheric testing 

and for early re-entry workers. 

NIOSH has responded to the finding (except as 

related to Matrix Comment 5) 

No further review of this item needed, except as related to issues in 

Section 5 below. 

NIOSH Response

See response to comment 5 below.

2 2 TBD does not provide adequate 

guidance for dose estimation to 

gonads, skin, and gastro-intestinal 

(GI) tract for early reactor test reentry personnel. Large hot-particle 

doses to skin and GI tract have not 

been evaluated. Naval Radiological 

Defense Laboratory (NRDL) 

documents and models have not 

been evaluated, though one 

document is referenced. 

NIOSH and SC&A agree that NRDL model 

could be used. NIOSH has been partially, but not 

fully, responsive to SC&A comments. 

Some review of this issue appears to be warranted. 

NIOSH Response

NIOSH has reviewed Hacker (1994) and has determined that much of the 

information contained within the book related to Rad-Safe operations and 

operation-specific radiological data represent condensed summaries on 

detailed information contained within operation-specific Nuclear Defense 

Agency reports which have been extensively reviewed and currently in 

the Site Research Data Base. The 2005 review of the NTS Site Profile 

included a statement that “Dr. Hacker’s book provides extensive 

references to primary documentation for the policies and controversies 

discussed in this paragraph (Hacker 1994, Note 52, pg. 327) that would 

be a very useful guide to the pressures that led to what appears to have 

been a significant compromise of the integrity of the external dose record 

in the early period.” Since 2005, NIOSH has extensively researched the 

integrity of the external dose record both for the atmospheric testing 

period and for the later underground testing activities in response to 

finding 13, Section 5.7.5 of SC&A 2005; Intentional Non-Use of 

Badges. This investigation did not detect a significant compromise of the 

integrity of the external dose record.

SC&A 2005 also stated the following: “There were also tensions between 

weapons testing and safety, at least in the early period. How this tension 

between safety and continued testing was resolved and what aspects of the 

resolution led to more safety and which ones to better public relations is a 

material issue that needs to be investigated as NIOSH prepares Rev. 01 of 

the NTS TBD. This is especially relevant since Elements of Controversy 

documents the “discontent” of the armed forces with AEC radiation 

exposure limits, which was the context in which the AEC relaxed its rules 

and allowed armed forces personnel to be present closer to the tests than 

previously allowed (Hacker 1994, pg. 92). Rad-Safe personnel would also 

have been present at the same locations as the armed forces personnel. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

2 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

Rad-Safe personnel generally preceded armed forces personnel into areas 

near ground zero. Both factors would tend to increase external and 

internal exposure.

Stationing personnel closer to ground zero also raises questions about the 

extent of neutron exposure during atmospheric testing that bear close

examination and analysis. As discussed above, NIOSH’s conclusion that 

personnel were not exposed to neutrons during nuclear weapons tests is 

premature at best. Study and analysis of primary documentation, 

including possibly still classified documentation about the tests, may be 

especially useful. Specifically, the possibility that troops (and hence RadSafe personnel) were stationed closer than permitted distances appears to 

be an important item of investigation.” NIOSH revised the NTS Site 

Profile (addressed in NTS-6 Rev 01, Sections 6.3.5.3.1, 6.3.5.3.3, 6.5.3, 

and Attachment in response to Finding 5.7.7 and 5.7.8 of SC&A 2005 to 

substantiate that neutron doses during atmospheric testing were negligible 

and not in error for some NTS workers.

SC&A 2005 also stated the following: “SC&A suggests that NIOSH make 

a careful assessment of Barton Hacker’s history and the sources that are 

cited in it insofar as they concern on-site radiation safety 

practices.” NIOSH has obtained a copy of Hacker 1994 and has reviewed 

it to understand the development of on-site radiation safety practices. The 

book will be entered into the Site Research Data Base for continuing 

review.

A recent review revealed that DOE dosimetry records supplied to NIOSH 

for NTS employees include reentry logs and survey information for 

employees involved in these types of activities. These activities would 

include tunnel reentries as well as reentry into the debris fields resulting 

from reactor experiments. A review of 42 case files for the NTS between 

(claim numbers redacted) of a sample of employee records has confirmed 

that of the 42, 23 contained these types of information (e.g., claim 

numbers redacted). Of the 19 cases that did not have additional 

monitoring records, they were individuals that did not routinely work in 

radiation areas (e.g., storekeeper, lineman, survey crew, bus driver, fry 

cook, field inspector, electronic tech, and truck driver). Therefore, for 

claimants documented to be involved in reentering the NRDS, NIOSH 

believes the reentry and survey information would be available which 

would allow the application of the NRDL model for exposure scenarios 

and experiments defined in Hazards To Personnel Re-entering the Nevada 

Test Site Following Nuclear Reactor Tests, NRDL-TR-68-149 (NRDL 

1968).
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

3 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

3 3 Doses from large (non-respirable) 

particles to GI tract and skin for 

workers in the early atmospheric 

test period have not been evaluated. 

These doses could be high. Hotparticle doses also need to be 

evaluated for early drillback and 

other early re-entry workers during 

underground testing periods. 

Hot particle exposure as a result of nuclear 

weapon tests is still outstanding for external dose 

and for oro-nasal breathing. 

It would appear useful to examine whether the NRDL model could also be 

used for weapons testing exposures to calculate partial doses.

NIOSH RESPONSE 

As described in the NRDL 1968 report, models developed for re-entry 

personnel supporting nuclear propulsion reactor test at the NRDS are not 

applicable to dose estimates for workers associated with atmospheric 

nuclear tests, drillbacks and tunnel re-entries following underground 

nuclear tests, or the accidental venting of underground nuclear tests. 

These models are based on 1) the expected fission density of the Phoebus 

2A, EP=II test which assumes a reactor run for twenty minutes at a power 

level of 5,000 MW, 2) an infinite field radioactivity measurement one 

hour post shutdown at three feet above the ground, and 3) a coarse particle 

(>12 microns diameter) ground deposition density of one particle per 

square meter. For potential hot particle exposure scenarios outside the 

NRDS (e.g., exposure to radioactive fallout from atmospheric testing, 

underground test that vented), these parameters are either unknown or 

unknowable. Therefore, any attempt to apply the NRDL models would 

undoubtedly introduce significant uncertainty in the calculated doses and 

NIOSH will not do so. However, any documented hot-particle NTS 

external exposures can be addressed through the procedures outlined 

OTIB-0017, OCAS-IG-001, and the VARSKIN model. Oro-nasal 

breathing is an overarching issue that will be evaluated on the project 

level – not specific to the NTS. As a result of the SEC determination for 

NTS, internal doses (from hot particles) are no longer estimated when 

bioassay data are absent. 

4 4 Ingestion of non-respirable hot 

particles by reactor testing and 

nuclear weapons testing workers 

due to oro-nasal breathing needs to 

be evaluated. 

It may be possible to calculate partial doses for 

certain non-presumptive cancers. 

The investigation of this issue will depend on how the Work Group 

decides to address matrix comments 2 and 3 above. 

NIOSH Response

See responses to items 2 and 3 above

As a result of the SEC determination for NTS, internal doses (from hot 

particles) are no longer estimated when bioassay data are absent. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

4 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

5 5 Resuspension model and 

resuspension factor are not 

scientifically defensible or claimant 

favorable, due to a variety of 

factors. Doses may be 

underestimated by an order of 

magnitude or more. Mass-loading 

approach would be preferable for 

internal dose. 

Matrix comments 6, 7, 15, and 23 are also 

covered here. NIOSH and SC&A are in 

agreement that occupational environmental dose 

can be estimated. NIOSH has not yet addressed 

some issues raised by SC&A. 

Review of unaddressed items appears to be warranted. 

NIOSH Response

The following assumptions (in black font) are excerpts from (Anspaugh 

2008). The replies to the assumptions are in light blue.

Assumption 1: No Contamination of the NTS Occurred after July 1962.

This assumption has already been examined extensively in the 

section of this document following the Introduction. As noted, there were 

many contaminating events that produced substantial new depositions on 

soil. The contribution of the Buggy event was even acknowledged in 

Rollins (2008a) although it was ignored. Events specifically mentioned in 

the reports of the environmental surveillance program were Pike, Nash, 

Hupmobile, Buggy, Door Mist, Schooner, and Baneberry. Events Buggy, 

Schooner, and Baneberry were even noted to have contaminated potable 

water at the NTS.

NIOSH Response

While it is true that there were many controlled and uncontrolled releases 

to the environment after 1962, the vast majority of these releases were of 

noble gases and volatile iodines which would not have contributed 

significantly to soil contamination (DOE 1996.)1 Of the non-volatiles 

reported (e.g., W-187, Sr-91, Cs-138, Ru-106, etc.), most had half-lives 

on the order of hours or days and would only be a concern to individuals 

participating in early reentry operations. As shown by Rollins (2007b), 

exposure to these short-lived fission and activation products would be 

expected to result in minimal doses to the non-presumptive cancers 

affecting the larynx (ET2 and LNET), skin, and prostate.

Also, it should be noted that DOE evacuated non-essential workers from 

downwind areas of the NTS prior to all tests to minimize potential for 

radiation exposure. In addition, after releases, surveys were conducted to 

characterize the fallout fields and to implement controls to prevent 

inadvertent entry into these areas. 

The only mention of potentially contaminated potable water was in 

December of 1968 and January, 1969 REECo (1971). The maximum 

concentration was 1.54 x 10-6uCi/cc measured on January 19, 1969 at the 

Area 2 Men’s Restroom. However, these elevated levels quickly 

dissipated and the mean concentration for all samples taken at this

location for 1969 was 4.60 x 10-9uCi/cc compared with 6.41 x 10-9uCi/cc 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

5 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

for 1968; well below the alert level of 1.0 x 10-7uCi/cc for unidentified 

radionuclides. Thus, anyone drinking water at this location during 1968 

and 1969 would be expected to receive inconsequential internal dose. 

1. DOE. Radiological Effluents Released From U.S. Continental 

Tests 1961 Through 1992. US Department of Energy Nevada 

Operations Office; DOE/NV-317 (Rev.1) UC-702; August 1996.

Assumption 2: The Air Concentrations Recorded by the Air 

Samplers of the NTS Environmental Surveillance 

Program During 1971 and Beyond Can Be Used to 

Derive the Air Concentrations That Would Have 

Been Seen at these Same Air-Sampler Locations 

During 1963–1970.

As demonstrated above by the detailed consideration of the 

contaminating events at NTS during 1963–1970 and the results of the 

environmental surveillance air-sampling program, there were several 

substantial excursions noted in the air concentrations due to massive 

releases at the NTS. The last such release occurred in December 1970. 

Thus, it is impossible for air-sampling results during the 1971–2001 

period to reproduce these massive excursions that occurred in 1963–

1970.

NIOSH Response

The purpose of the calculations performed by Rollins (2007b) was not to 

try to predict air sampler measurements between 1963 and 1970 but was 

to provide a claimant favorable method of assigning environmental 

intakes to individuals not associated with operations. This was done by 

selecting the highest integrated air concentration measured for Pu-239, as 

part of the environmental surveillance program, anywhere on site between 

1971 and 2001 and correlating it with other radionuclides (decay 

corrected) persisting in the NTS soils across the site to estimate their 

relative intakes. NIOSH believes the “massive excursions” that occurred 

as a result of controlled and uncontrolled releases are relatively 

unimportant to organ dose because of their brief duration and because 

nonessential personnel were not exposed to them due to the required, pretest, downwind evacuations.

Assumption 3: More Generally, the Air Concentrations Recorded 

by the Air Samplers of the Environmental 

Surveillance Program Represent the Air 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

6 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

Concentrations Actually Experienced by the 

Workers at the NTS.

This is a more difficult issue, as there do not appear to be any 

objective data on the inhalation of radionuclides at the NTS as measured 

with a personal air sampler and in comparison to any of the locations of 

the environmental surveillance network.

It is known, however, that these air-sampling stations were 

typically located next to cafeterias and dispensaries, where there would 

be relatively little dust. On the other hand, there were many types of work 

that would have raised large amounts of dust. One outstanding example 

of a major dust raising event was the movement of drilling rigs, such as 

the one shown in Fig. 18, from one location to another without 

disassembly. The drill rig was raised with hydraulic jacks, and large steel 

beams were placed through the rig. Then four “coasters,” one of which is 

shown in Fig. 19, were attached to the beams. The two beams and one of 

the coasters are shown in Fig. 20. The presumed path of one such 

movement is shown in Fig. 21.

There has been substantial concern about mass loading and 

exposure to persons, if there might be a volcanic eruption that would 

influence the Yucca Mountain waste-storage site. As part of the 

evaluation process, there has been a substantial effort to evaluate possibly 

enhanced mass loading due to outdoor activities in a post eruption 

environment. The evaluation has consisted of reviewing relevant 

literature and in conducting measurements of mass loadings in Amargosa 

Valley, Nevada. These studies are described in Bechtel SAIC (2006).

The authors of Bechtel SAID (2006) considered mass loadings in 

several environments; two of interest to us are the “Inactive Outdoor 

Environment,” which would be similar to the locations where the NTS 

environmental surveillance air samplers were located. Their review of 

data and of measurements made as part of the Yucca Mountain evaluation

program resulted in their description of mass loading in this environment 

with a triangular distribution with a mode of 0.060 mg m-3, a minimum of 

0.025 mg m-3, and a maximum of 0.100 mg m-3.

The “Active Outdoor Environment” was also considered, and 

would include activities such as driving bulldozers, tractors, heavy 

construction machinery, etc. Their evaluation of literature values and of 

their contracted measurements in Amargosa Valley was again a 

description by a triangular distribution, but now with a mode of 3 mg m-3, 

a minimum of
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

7 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

1 mg m-3, and a maximum of 10 mg m-3.

Thus, according to the evaluation of the Yucca Mountain 

evaluation group, the mass loading experienced by a bulldozer driver 

would be on the order of 3 divided by 0.06, or 50 times higher than the 

concentration of dust in an inactive outdoor environment. Of course, a 

person driving a bulldozer would not be exposed to such levels 100% of 

the time, but it is obvious that a stationary air sampler located next to a 

cafeteria or dispensary would not give a realistic indication of a working 

person’s exposure.

It is also well to remember the words of some of the early 

investigators of the NTS environmental surveillance program:

“Results of environmental surveillance in 

sampling activity values cannot be used in calculating 

personnel exposure doses.”

As a final point, it has often been assumed by NIOSH personnel 

that “Controlled Areas” at the NTS are fenced and that it not possible to 

enter such areas. This is hardly the case, as many Controlled Areas are 

“controlled” by nothing more than a warning sign. Fig. 22 is a photo of 

one such Controlled Area, which actually has a road right through it.

NIOSH Response

As stated above, the purpose of the calculations performed by Rollins 

(2007b) was not to try to predict intakes associated with operational 

activities but was to provide a claimant favorable method of assigning 

environmental intakes to individuals not associated with operations. 

Therefore, it would be reasonable to position the samplers (cafeterias and 

dispensaries) where they would be unlikely to be exposed to dust clouds 

associated with operational activities (e.g., moving drilling rigs).

Assumption 4: There Were No Clean-Ups of Radioactive Materials 

Between 1962 and the Time Period When 

Measurements of Surface Radionuclides Were Made 

by the Radionuclide Inventory and Distribution 

Program (RIDP in the 1980s.

The measurements of surface-soil contamination performed by 

investigators of the RIDP are critical to the methodology developed in 

Rollins (2008a) for the reconstruction of internal doses via both 

inhalation and incidental ingestion of soil. The RIDP measurements were 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

8 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

not made for the purpose of reconstructing doses, but rather for defining 

the amounts and locations of existing contamination for the purposes of 

control and future clean-up (Kordas and Anspaugh 1982). Between 1962 

and the time of the measurements made by the investigators of the RIDP, 

there was an active program on cleaning up contaminated soil.

McArthur and Mead (1989) specifically mention that much of the 

Nuclear Rocket Development Station in Area 25 had been cleaned up 

before the RIDP measurements were started in February 1984.

Thus, the fourth assumption must be considered as invalid, as 

well. The surface soil activities measured in the 1980s cannot be 

depended upon to represent activity present in 1963–1970, decay 

corrected or not.

NIOSH Response

McArther (1991) identified a total of 510 square miles of contaminated 

soils (about a third of the total NTS area) containing more than 2,000 

curies of radioactivity. This radioactivity was related to radionuclides that 

are persistent in the environment and are important to organ dose. 

Although there were efforts to decontaminate some of the more highly 

contaminated areas, these efforts focused on contaminated equipment and 

large, nonrespirable particles. The efforts made to decontaminate Nuclear 

Rocket Development Station in Area 25 would likely have had little effect 

on the air concentrations measured in Area 7 that were used to estimate 

environmental intakes.

6 5 The use of the site average air 

concentration values when worker 

location is not known is not 

claimant favorable. Largest value 

consistent with job-type data should 

be used in such cases. 

See matrix comment 5 above. See matrix comment 5 above. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

9 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

7 5 Resuspension doses to monitored 

workers, especially early re-entry 

workers, may be underestimated, 

due to the presence of short-lived 

radionuclides and higher 

resuspension expected in the days 

and months after a test (including 

safety tests). TBD does not specify 

procedures for estimating 

environmental internal doses in 

such cases. 

See matrix comment 5 above. See matrix comment 5 above. 

8 6 Use of 1967 external dose data for 

1963–1966 is not claimant 

favorable. There was no test in 

1967 with measurable offsite 

fallout. Relatively short-lived 

radionuclides, which were likely 

present in 1963–1966, would have 

substantially decayed away by 

1967. 

NIOSH has pointed out that badging was 

required for all workers after 1957. 

No further review of this comment appears to be needed. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

10 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

9 6 Lack of environmental external 

dose data for 1968–1976 is 

puzzling. TBD has not specified an 

approach to estimating external 

environmental dose for this period. 

Venting in the 1968–1970 period 

likely made external dose in that 

period (and possibly beyond) higher 

than 1967. 

See matrix comment 8 above. See matrix comment 8 above. 

10 7 The TBD does not provide any 

guidance for pre-1963 external 

environmental dose. Issues relating 

to unmonitored workers, as well as 

time of entry into contaminated 

areas, could be important. 

SC&A has not reviewed the pre-1957 dose 

assignments suggested by NIOSH. Suggested 

dose assignments do not appear claimant 

favorable or compatible with the MDLs. 

SC&A’s preliminary conclusion is that NIOSH values may reflect 

subtraction of the badge MDL. NIOSH clarification on how the values 

were derived is needed. Review of the proposed dose assignments appears 

to be warranted. 

NIOSH Response

The values in Table 6-11 of Nevada Test Site-Occupational External Dose

(ORAUT-TKBS-0008-6, Rev 03) represent an analysis of recorded dose 

values for the years indicated in the table. In order to provide a complete 

and claimant-favorable listing of coworker dose, Table 6-11 will be 

revised with respect to the methodology given in Use of Coworker 

Dosimetry Data for External Dose Assignment (ORAUT-OTIB-0020). 

Using this guidance, missed dose equal to [(N-1) *LOD] for a given year 

(where N is the exchange frequency) will be added to the recorded dose 

values for the 50th and 95th percentile values in Table 6-11 respectively. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

11 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

11 8 Correction factors for external 

environmental dose due to 

geometry of organ relative to badge, 

and angular dependence of the dose 

conversion factor need to be 

developed. 

NIOSH has provided a table of the photon energy 

spectra to be used. NIOSH’s photon energy 

groupings may not apply to nuclear testing 

spectra. NIOSH concluded that the external dose 

conversion factors would not make a material 

difference and hence do not need to be applied. 

NIOSH’s photon energy groupings appear to need review. The correction 

factors for skin dose may be much greater than one. SC&A’s preliminary 

view is that some aspects of NIOSH’s conclusions of external 

environmental dose correction factors need review to assure that they are 

claimant favorable. 

NIOSH Response

The issues regarding correction factors for skin dose are addressed by 

using the beta:gamma methodologies summarized in Section 6.4.2.1 and 

discussed in detail in Attachment C of Nevada Test Site-Occupational 

External Dose (ORAUT-TKBS-0008-6, Rev 03). Please note that 

Attachment C discussed beta:gamma ratio recommendations for 

geometries involving point sources, contaminated surfaces, and 

immersion in contaminated clouds. Based on the availability claimantinterview data and work history files, dose reconstructors can choose the 

general guidance from section 6.4.2.1 (which includes an estimate of 

uncertainty) or specific guidance given by the detailed data in Attachment 

C. Finally, the photon energy groupings discussed in OCAS-IG-001 and 

given again in Attachment B of ORAUT-TKBS-0008-6 are driven by the 

available energy ranges in IREP, which is used to calculate probability of 

causation.

12 9 Radon doses in G-Tunnel are not 

claimant favorable. Gravel Gertie 

radon doses are not discussed, and 

could be substantial. (Site status of 

Gravel Gertie workers needs 

clarification.) 

NIOSH has addressed G-Tunnel issue. 

Clarification is needed on Gravel Gerties.

NIOSH should clarify whether Gravel Gerties were entered in the post1992 period. If not, this issue is resolved. 

NIOSH Response

For non-presumptive cancers (e.g., larynx) during all periods and 

presumptive cancers (e.g., lung) after 1992, exposure to radon and thoron 

will be calculated and assigned in accordance with ORAUT (2010a) when 

records indicate the claimant made entries into the Gravel Gerties.
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

12 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

13 10 Environmental doses due to I-131 

venting need to be taken into 

account for non-monitored workers. 

NIOSH’s method for estimating I-131 exposure 

due to Baneberry venting does not appear to be 

claimant favorable. A similar approach for other 

ventings may also underestimate dose. 

Development of a method for assigning more claimant-favorable partial I131 doses appears to be warranted. 

NIOSH Response

A review of the personnel decontamination efforts following the 

Baneberry event indicated that of the 900 individuals evacuated from 

forward areas following the event, 145 underwent decontamination and 

submitted bioassay samples. These sample results would be available for 

internal dose reconstruction.

Another 69 individuals underwent prompt thyroid counts and all but 17 of 

these workers were assigned doses to their thyroids which are included in 

the dosimetry records and are available for dose reconstruction. 

A review of the technical Basis for Internal Dosimetry at the Nevada Test 

Site dated 1993 (SRDB Ref. ID 1948) indicated that the minimum 

detectable dose for the prompt thyroid counter was less than 0.001 rem for 

I-131, 132, and 133. It is reasonable to assume that the 17 workers that 

had calculated doses of zero likely had thyroid doses < 0.001 rem.

NIOSH believes that the DOE decontamination efforts following the 

Baneberry event identified several workers with a potential for internal 

exposure and that the doses assigned were appropriate for the techniques 

in use at the time. The bioassay sample results for those individuals 

assigned internal dose are contained in the dosimetry records and will be 

available for future dose reconstruction as needed. For workers that may 

have been involved with the Baneberry incident but have no bioassay 

results in their dosimetry records, as a result of the SEC class for NTS, 

NIOSH has determined, and the Secretary of Health and Human Services 

has concurred that internal doses cannot be reconstructed between January 

27, 1951 and December 31, 1992, inclusive, for the energy employee.

NIOSH agrees that the bounding calculation currently contained in 

ORAUT-TKBS-0008-5 may not be appropriate and will replace that 

discussion with the one above.

NIOSH has responded to the issue of contaminated potable water in 

Section 5.4 above.

14 11 There are no internal monitoring This issue has been resolved, due to granting of This issue can be closed. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

13 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

data until late 1955 or 1956; some 

Pu from then on; some tritium from 

1958; Pu, T, and mixed fission 

products from 1961; and full 

radionuclide coverage established 

in about 1967. The TBD does not 

provide significant guidance for 

estimating internal dose for the pre1967 periods for many 

radionuclides. 

the SEC up to the end of 1992. NIOSH uses 

available individual internal dose data for partial 

dose estimation. 

15 12 

(details 

in 

Section 

5) 

Resuspension of radionuclides by 

the blast wave, fractionation of 

relatively non-volatile 

radionuclides, and the variability of 

Cs-137 to Sr-90 ratios need to be 

taken into account in internal dose 

estimation. 

See matrix comment 5 above. See matrix comment 5 above. 

16 13 Use of photon dose, as done by 

Defense Threat Reduction Agency 

(DTRA), as the basis for estimating 

internal dose during periods when 

there are no data or scattered 

internal monitoring data has 

significant uncertainties. These 

uncertainties are compounded by 

the data integrity issue associated 

with NTS (see comment 20 below). 

This issue has been resolved by the granting of 

the SEC. 

This issue can be closed. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

14 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

17 14 Ingestion doses need to be better 

evaluated. 

NIOSH had suggested the use of ORAUT-OTIB0018. This is not applicable to outdoor NTS 

work. 

NIOSH should consider partial ingestion dose estimation based on 

resuspension models. See Section 5 above. 

NIOSH Response

Current practice for reconstructing internal dose at the NTS does not 

include the application of OTIB-0018 methods. However, ingestion doses 

are determined using methods described in ORAUT 2008b. These 

methods assume the ingestion of 100 mg per day of (soil which is twice 

the amount recommended by the EPA [1989])1contaminated to the 

highest levels measured for all areas at the site excluding Area 30. 

Although Area 30 provided the highest levels of contaminated soil, it was 

not included in the consideration for soil ingestion because of its size 

(0.03 sq. mile), remoteness, and inaccessibility (ORAUT 2008b). The 

ingestion model described in ORAUT (2008b) includes decay correction 

back to 1963 and organ-specific corrections for exposure to early fission 

and activation products from 1963 through 1970.

It should be noted that the calculation of environmental intakes through 

the inhalation pathway was not based on a resuspension model but rather 

on maximum measured atmospheric concentrations of Pu-239. For the 

inhalation intakes, a resuspension model was only used to estimate 

increased resuspension factors realized during early times after initial 

deposition. This phenomenon would not be important to ingestion 

intakes.

1. EPA (U.S. environmental Protection Agency), 1989, Risk 

Assessment Guidance for Superfund. Vol.1 Human Health 

Evaluation Manual, Part A, EPA/540/1-89/002, Office of 

Emergency and Remedial Response, Washington D.C. [SRDB 

Ref. ID: 35528]

18 15 Recommended use of ORAUTOTIB-0002 for post-1971 tunnel reentry workers is contrary to 

guidance in that document, and its 

scientific validity has not been 

established. Its use may not be 

satisfactory even with restrictions, 

for instance for reactor testing early 

re-entry workers. 

This issue has been resolved by the granting of 

the SEC. 

This issue can be closed. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

15 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

19 16 There are no beta dose data until 

1966; the TBD does not specify a 

procedure for estimating pre-1966 

beta dose. When the approach is 

developed, the large hot-particle 

issue will need to be taken into 

account. 

NIOSH suggests the use of beta:gamma ratios. 

SC&A agrees in principle, but some suggested 

ratios may not be claimant favorable. 

Review of the beta:gamma ratios suggested by NIOSH appears to be 

warranted. 

NIOSH Response

Please see the response on comment 11 for a discussion of the variety of 

approaches that are available for dose reconstructors to address the 

assignment of beta dose. NIOSH can address specific issues once a full 

review is done by SC&A.

20 17 There appears to have been 

intentional non-use of badges in 

some circumstances to avoid 

approaching or exceeding 

operational dose limits. The 

practice may have occurred until 

the mid-1960s or even extended 

into the 1970s. NIOSH has not 

investigated this problem, which 

raises questions on the integrity of 

the external dose record possibly 

into the 1970s, which need to be 

explicitly addressed. 

This issue was extensively researched and 

discussed during the SEC review process. 

In SC&A’s view, this issue can be closed. 
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

16 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

21 18 The TBD does not contain 

information about extremity 

dosimetry. Site status of bomb 

assembly workers is unclear. 

According to NIOSH, there were no claims of 

device assembly workers involving extremity 

cancers as of 2007. 

An update of claims with non-covered cancers to check whether there are 

still no extremity cancer claims through 2012 would be useful. 

NIOSH Response

Current practice for dose reconstruction includes the evaluation 

of extremity dose when these data are provided in the dosimetry 

records. Evaluation of extremity dose is typically performed to 

determine the appropriateness of the application of glove box 

factors (dose to the prostate and gonads) and to determine 

claimant favorable doses applicable to skin cancers appearing on 

the hands and forearms. In rare cases where extremity 

monitoring included other parts of the body such as the head, an 

evaluation would be made to determine appropriate adjustments 

necessary to cancers appearing above the shoulders (e.g., larynx). 

Therefore, when cases of device assembly workers require dose 

reconstruction, the extremity doses will be evaluated for 

application to cancers appearing on the extremities.

22 19 There are no neutron dose data until 

1966, and partial data until 1979. 

TBD assertion that neutron doses 

during atmospheric testing were 

negligible has not been 

substantiated and may be in error 

for some workers. 

NIOSH’s analysis regarding the low exposure 

potential for Department of Energy (DOE) and 

contractor test personnel appeared reasonable. 

There are still some outstanding questions, e.g. 

choice of n/p ratios. 

Some further review of this issue appears to be warranted on specific 

points (e.g., n/p ratios for device assembly workers). 

NIOSH Response

Although the N:P ratio for nuclear device assembly workers can vary, the 

recommended value from Pantex can be applied as a reasonable value to 

use given the variety of devices and workplace geometries. Information 

regarding TRU handling and handling of neutron sources is provided in 

Tables 6-9, 6-15, and 6-16 of Nevada Test Site-Occupational External 

Dose (ORAUT-TKBS-0008-6, Rev 03). NIOSH can address specific 

issues if a further review is done by SC&A with respect to the post-1992 

period.
Effective Date:

December 14, 2012

Revision No.

1 (Draft)

Document No.

SCA-SP-IM2012-0042

Page No.

17 of 17

NOTICE: This report has been reviewed for information protected by the Privacy Act and has been cleared for distribution to members of the public. 

DRAFT ORAUT/NIOSH responses 01/30/2014

Comment

Number 

Report 

Section Issue Description Status SC&A Preliminary Conclusions

23 20 

(Details 

in 

Section 

5) 

Adequacy of soil data for 

estimating resuspension doses 

needs to be evaluated, for instance 

in relation to hot spot detection and 

Pu soil data. 

See matrix comment 5 above. See matrix comment 5 above. 

24 21 The presence of high-fired oxides 

resulting from atmospheric 

weapons testing and reactor testing 

needs to be investigated. 

This issue has been resolved due to the granting 

of the SEC. 

This issue can be closed. 

25 22 NOISH documentation of site 

expert interviews is inadequate, and 

crucial site expert interviews have 

not been performed or performed in 

an incomplete manner, notably 

Barton Hacker and [Redacted]. 

Potentially critical archives and 

documents have not been reviewed, 

including the NRDL and Barton 

Hacker primary reference materials. 

NIOSH has extensively modified its interview 

documentation approach. 

This issue is now part of Worker Outreach review. 

26 23 A number of issues in relation to 

waste handling, decommissioning, 

and other post-1992 site activities 

were reviewed by SC&A in SC&A 

2005 or during the SEC review. 

This is a new matrix comment. It has been added 

to this matrix update as a placeholder for WG 

discussion.